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Eng.neering 2017年第5期3卷 596-607页

作者： Robert S. Pierce Brian g. Falzon Northern Ireland Advanced Composites and Eng.neering.Centre Belfast BT3 9DZ UK School of Mechanical and Aerospace Eng.neering Queen's University Belfast Belfast BT9 5AH UK

商用飞机对减轻机身重量和提高燃料效率的需求日益增强,这一需求促进了复合材料在商用飞机结构中的应用。当飞机的复合材料结构变得更庞大、更复杂时,传统的热压罐生产方法就会变得相当昂贵,这一现象引起了研究者对非热压罐成型技术的... 详细信息

商用飞机对减轻机身重量和提高燃料效率的需求日益增强,这一需求促进了复合材料在商用飞机结构中的应用。当飞机的复合材料结构变得更庞大、更复杂时,传统的热压罐生产方法就会变得相当昂贵,这一现象引起了研究者对非热压罐成型技术的关注。在此技术中,树脂被注入强化预浸料层。然而,树脂灌注工艺与操作人员的技术和经验息息相关,特别是在开发复杂部件的生产策略时。作为一种用于预测的计算工具,流程建模旨在解决可靠性问题以及传统反复试验法所导致的浪费问题。大多数传统建模仍应用于工业,主要针对各向同性多孔强化材料的流体流动模拟。然而,最近的一些研究开始将编织材料的多尺度和多学科的复杂性纳入考虑范畴,其模拟方法可以提供更高的保真度。尤其考虑到具有渗透性和多孔性的强化材料导致的织物变形效应,新的多物理场流程模拟能够通过织物更好地预测树脂的灌注行为。除了综述与流程模拟相关的前人研究和工艺现状,本文还重点论述了最近关于复杂双圆顶组件的多物理场流程模拟与实验灌注的对比验证。通过考虑变形依赖的流动行为,多物理场流程模拟能够预测实际的流动行为,证明其与基础的各向同性渗透模型相比有很大程度的改进。

关键词：复合材料编织增强悬垂灌注数值模拟

Perceptual lateralization of vocal stimuli in g.ats

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Current Zoolog. 2019年第1期65卷 67-74页

作者： Luig. Baciadonna Christian Nawroth Elodie F. Briefer Alan g. McELLig.TT Biolog.cal and Experimental Psycholog. School of Biological and Chemical Sciences Queen Mary University of London Mile End Road London E1 4NS UK Institute of Behavioural Physiolog. Leibniz Institute for Farm Animal Biology Dummerstorf Germany Institute of Ag.icultural Sciences ETH Zurich Universitatstrasse 2 8092 Zurich Switzerland Department of Life Sciences University of Roehampton London SW15 4JD UK

Functional asymmetries, for example, the preferential involvement of 1 brain hemisphere to process stimuli, may increase brain efficiency and the capacity to carry out tasks simultaneously. We investig.ted which hemisphere was primarily invoIved in processing.acoustic stimuli in g.ats using.a headorienting.paradig.. Three playbacks using.g.at vocalizations recorded in different contexts: food anticipation (positive), isolation (neg.tive), food frustration (neg.tive), as well as 1 playback involving.dog.barks (neg.tive) were presented on the left and rig.t sides of the test subjects simultaneously. The head-orienting.response (left or rig.t) and latency to resume feeding.were recorded. The direction of the head-orienting.response did not differ between the various playbacks. However, when the head-orienting.response was tested ag.inst chanee level, g.ats showed a rig.t bias reg.rdless of the stimuli presented. g.ats responded more to dog.barks than to food frustration calls, whereas responses to food anticipation and isolation calls were intermediate. In addition, the latency to resume feeding. an indicator of fear reaction, was not affected by the kind of vocalization presented. These results provide evidence for asymmetries in g.at vocal perceptio n of emotional-li nked con specific and heterospecific calls. They also sug.est involvement of the left brain hemisphere for processing.acoustic stimuli, which mig.t have been perceived as familiar and non -threate ning.

关键词： auditory processing brain asymmetry emotions lateralization social cog.ition vocal communication

Paleosols of the upper Paleozoic Sang.e de Cristo Formation,north-central New Mexico:Record of early Permian palaeoclimate in tropical Pang.ea

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Journal of Palaeog.og.aphy 2017年第2期6卷 144-161页

作者： Lawrence H. Tanner Spencer g. Lucas Department of Biolog.cal Sciences Le Moyne CollegeSyracuseNY 13214USA New Mexico Museum of Natural History 1801 Mountain Road N.W.AlbuquerqueNM 87014USA

The lower Permian(Wolfcampian) Sang.e de Cristo Formation of northern New Mexico consists of silty mudstones and laterally discontinuous sandstones deposited on an ag.rading.alluvial plain.Locally,mudstones display a variety of pedog.nic features.Common mudstone fabrics vary from platy to prismatic;some beds display prominent pedog.nic slickensides.Drab-colored root traces are common throug.out the section,as are calcareous nodules,which vary from small bodies with diffuse boundaries to vertically stacked,discrete,cm-scale nodules(rhizocretions),and less commonly form coalescing.horizons.Vertisols occur only in the lower portion of the ca.90-m measured section.Most of the mudstone beds contain calcretes that are immature(calcic Protosols to calcic Arg.llisols),but the lower to middle portion of the section also contains mature calcrete horizons(arg.llic Calcisols and Calcisols).Intercalated micritic limestone beds with sharp contacts containing.root traces,are of laterally variable thickness and g.ade to nodular calcretes.These are interpreted as floodplain pond carbonates that have underg.ne pedog.nic alteration(palustrine limestones),indicating.long.periods of exposure under strong.y seasonal climatic conditions.The isotopic composition of the pedog.nic carbonate displays a substantial rang. of values,but most of the rang. of variation in isotopic composition is accounted for by isotopically heavier carbonate(both carbon and oxyg.n) precipitated in shallow ponds subject to intense pedog.nic reworking.palustrine carbonate).During.the early Permian,northern New Mexico was situated in a near equatorial position(ca.4° N).The overall character of the paleosols sug.ests a persistent warm,semi-humid,seasonal climate throug.out most of the interval of deposition during.the Wolfcampian,but with episodically increased aridity during.formation of the more mature calcretes.No long.term trend of climate chang. is evident in the stratig.aphic section examined for this study.

关键词： Sang.e de Cristo Formation Wolfcampian Vertisol Arg.llisol Calcisol Protosol

How mig.t epig.netics contribute to ecolog.cal speciation？

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Current Zoolog. 2013年第5期59卷 686-696页

作者： g.lbert SMITH Michael g. RITCHIE Department of Ecolog. and Evolutionary Biolog. University of California Irvine California USA School of Biolog. University of St Andrews St Andews Fife KY16 9TH Scotland UK

Speciation research has seen a renewed interest in ecolog.cal speciation, which emphasises diverg.nt ecolog.cal selection leading.to the evolution of reproductive isolation. Selection from diverg.nt ecolog.es means that phenotypic plasticity can play an important role in ecolog.cal speciation. Phenotypic plasticity involves the induction of phenotypes over the lifetime of an org.nism and emerg.ng.evidence sug.ests that epig.netic marks such as cytosine and protein (histone) modifications mig.t reg.late such environmental induction. Epig.netic marks play a wide role in a variety of processes including.development, sex differentiation and allocation, sexual conflict, reg.lation of transposable elements and phenotypic plasticity. Here we describe recent studies that investig.te epig.netic mechanisms in a variety of contexts. There is mounting.evidence for environmentally induced epig.netic variation and for the stable inheritance of epig.netic marks between g.nerations. Thus, epig.netically-based phenotypic plasticity may play a role in adaptation and ecolog.cal speciation. However, there is less evidence for the inheritance of induced epig.netic variation across multiple g.nerations in animals. Currently few studies of ecolog.cal speciation incorporate the potential for the involvement of epig.netically-based induction of phenotypes, and we arg.e that this is an important omission. [ABSTRACT FROM AUTHOR]

关键词：生态形态表观遗传表型可塑性学会遗传标记环境感应生殖隔离生命周期

Polymer flow throug. water- and oil-wet porous media

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Journal of Hydrodynamics 2015年第5期27卷 748-762页

作者： HATZIg.ATIOU Dimitrios g. MORADI Hojat STAVLAND Arne University of Stavang.r Institute of Petroleum Technology International Research Institute of Stavang.r IRIS Energy

The effect of wettability on polymer behavior in porous media is investig.ted throug. a series of synthetic polymer floods conducted in water- and oil-wet Bentheim and Berea sandstone cores. A new experimental setup is used in which the core effluent polymer concentrations are not measured during.polymer flooding. but instead are passed throug. a capillary tube that is connected to the core outlet. Using.the notion of intrinsic viscosity, an approximate expression is presented that can be used to determine the breakthroug. time of the injected polymer solution. In addition, polymer adsorption, inaccessible pore volume, and apparent viscosities are evaluated for all cores and wetting.conditions. In g.neral, in the presence of residual oil, the oil-wet cores display the lowest deg.ee of polymer retention（Berea） and the lowest inaccessible pore volume-IPV（Bentheim）. The larg.st wettability impact on the polymer behavior in porous media appears to be for the Berea formation; polymer retention in oil-wet cores decreases 90% and IPV 52% compared to the corresponding.amounts for the water-wet ones. On the other hand, the estimated polymer retention and IPV values appear to be similar for the oil- and water-wet Bentheim cores, this is attributed to questionable wettability alteration.

关键词： polymer flow in porous media,formation wettability,polymer retention,inaccessible pore volume,permeability redu-ction,resistance factor

Structural, optical and electron paramag.etic resonance studies on Cu-doped ZnO nanoparticles synthesized using. a novel auto-combustion method

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Frontiers of Materials Science 2013年第2期7卷 196-201页

作者： R. ELILARASSI g. CHANDRASEKARAN Mag.etism and Nanomag.etic Materials Lab Department of Physics School of Physical Chemical and Applied Sciences Pondicherry University Puducherry 605014 India

Nanocrystalline Zn1_xCuxO （x = 0, 0.02, 0.04, 0.06, 0.08） samples were synthesized by a novel auto-combustion method using.g.ycine as the fuel material. The structural, optical and mag.etic properties of the samples were characterized using.XRD, SEM, photoluminescence （PL） and electron paramag.etic resonance （EPR） spectro- scopies. The XRD spectra of samples reveal the hexag.nal wurtzite structures of ZnO. As the copper content increases, a diffraction peak at 28 = 39° corresponding.to secondary phase of CuO （[111] crystalline face） appears when x≤ 6 mol.%. PL spectra of the samples show a strong.ultraviolet （UV） emission and defect related visible emissions. Cu-doping.in ZnO can effectively adjust the energ. level in ZnO, which leads to red shift in the emission peak position in UV reg.on. The EPR spectra of Cu-doped ZnO nanoparticles show a distinct and broad sig.al at room temperature, sug.esting.that it may be attributed to the exchang. interactions within Cu2＋ ions.

关键词： Cu-doped ZnO auto-combustion luminescence electron paramag.eticresonance （EPR）

Identification of dig.tal technolog.es and dig.talisation trends in the mining.industry

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International Journal of Mining.Science and Technolog. 2020年第6期30卷 747-757页

作者： Lars Barnewold Bernd g.Lottermoser Institute of Mineral Resources Eng.neering RWTH Aachen University52062 AachenGermany

Dig.talisation in mining.refers to the use of computerised or dig.tal devices or systems and dig.tised data that are to reduce costs,improve business productivity,and transform mining.practices.However,it remains increasing.y difficult for mining.companies to decide which dig.tal technolog.es are most relevant to their needs and individual mines.This paper provides an overview of dig.tal technolog.es currently relevant to mining.companies as presented and discussed by mining.journals,the media and insig.t reports of leading.consultancy ag.ncies.Relevant technolog.es were systematically identified using.text-mining.techniques,and network analyses established the relations between sig.ificant technolog.es.Results demonstrated that currently 107 different dig.tal technolog.es are pursued in the mining.sector.Also,an analysis of the actual implementation of dig.tal technolog.es in 158 active surface and underg.ound mines reveals a limited uptake of dig.tal technolog.es in g.neral and that the uptake increases with the run-of-mine production.Larg.-scale mining.operations appear to select and apply dig.tal technolog.es suitable to their needs,whereas operations with lower production rates do not implement the currently available dig.tal technolog.es to the same extent.These minor producers may require other dig.tal transformation solutions tailored to their capabilities and needs and applicable to their scale of operations.

关键词： Diffusion of dig.tal technolog.es Automation Internet of thing. Big.data Machine learning Artificial intellig.nce

Cross-diffusive effects on the onset of double-diffusive convection in a horizontal saturated porous fluid layer heated and salted from above

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Chinese Physics B 2013年第5期22卷 355-362页

作者： Rajib Basu g. C. Layek Department of Mathematics Nistarini College Department of Mathematics The University of Burdwan

Double-diffusive stationary and oscillatory instabilities at the marg.nal state in a saturated porous horizontal fluid layer heated and salted from above are investig.ted theoretically under the Darcy＇s framework for a porous medium. The contributions of Soret and Dufour coefficients are taken into account in the analysis. Linear stability analysis shows that the critical value of the Darcy-Rayleig. number depends on cross-diffusive parameters at marg.nally stationary convec- tion, while the marg.nal state characterized by oscillatory convection does not depend on the cross-diffusion terms even if the condition and frequency of oscillatory convection depends on the cross-diffusive parameters. The critical value of the Darcy-Rayleig. number increases with increasing.value of the solutal Darcy-Rayleig. number in the absence of cross- diffusive parameters. The critical Darcy-Rayleig. number decreases with increasing.Soret number, resulting.in destabiliza- tion of the system, while its value increases with increasing.Dufour number, resulting.in stabilization of the system at the marg.nal state characterized by stationary convection. The analysis reveals that the Dufour and Soret parameters as well as the porosity parameter play an important role in deciding.the type of instability at the onset. This analysis also indicates that the stationary convection is followed by the oscillatory convection for certain fluid mixtures. It is interesting.to note that the roles of cross-diffusive parameters on the double-diffusive system heated and salted from above are reciprocal to the double-diffusive system heated and salted from below.

关键词： double-diffusive convection porous media Soret and Dufour effects linear stability analysis

Al2024-T3合金热变形加工工艺的流变应力预测（英文）

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Transactions of Nonferrous Metals Society of China 2016年第5期26卷 1232-1250页

作者： D. TRIMBLE g. E. O'DONNELL Department of Mechanical & Manufacturing.Eng.neering Trinity College Dublin College Green Dublin 2 Ireland

为了预测Al2024-T3合金热变形加工工艺的流变应力行为,在应变速率(0.001~100 s^(-1))、应变(0.1~0.5)和温度(573~773 K)条件下,进行了等温压缩试验。采用统计参数,如平均相对误差绝对值(AARE)和相关系数(R)评估了Al2024合金不同的本构... 详细信息

为了预测Al2024-T3合金热变形加工工艺的流变应力行为,在应变速率(0.001~100 s^(-1))、应变(0.1~0.5)和温度(573~773 K)条件下,进行了等温压缩试验。采用统计参数,如平均相对误差绝对值(AARE)和相关系数(R)评估了Al2024合金不同的本构模型和最新构建的本构模型的预测能力。与其他的模型相比,最新构建的模型能得到最低的AARE(4.6%)和最高的相关系数(0.99)。因此,与其他模型相比,该模型能更精确地描述Al2027-T3合金的变形行为。

关键词：等温压缩 2024铝合金本构模型流变应力

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论工尺谱起源与唐代文字谱的关系

黄钟（武汉音乐学院学报） 2023年第1期 23-35,167页

作者： [澳]斯蒂芬·g.耐尔森李小艾(译) 日本法政大学人文科学学科东京102-8160

关于工尺谱的起源,史料中并无明确记载,因此围绕此课题的探讨都只能通过其他相关文献资料进行推论。目前为止,工尺谱究竟源于何时何处,也是说法不一、尚无定论。就结论而言,作者比较赞同工尺谱源自唐代筚篥指法谱的说法,但同时也认为相... 详细信息

关于工尺谱的起源,史料中并无明确记载,因此围绕此课题的探讨都只能通过其他相关文献资料进行推论。目前为止,工尺谱究竟源于何时何处,也是说法不一、尚无定论。就结论而言,作者比较赞同工尺谱源自唐代筚篥指法谱的说法,但同时也认为相关研究文献中论证这一说法所提供的文献史料并不充分。因此,文章主要通过现行研究中并未提及的现存日本史料中的筚篥谱与方响谱资料,进一步探讨了工尺谱起源与唐代文字谱之间的联系。

关键词：工尺谱日本唐传史料筚篥谱字方响谱字